Agri-environment schemes are an increasingly important tool for the maintenance and restoration of farmland biodiversity in Europe but their ecological effects are poorly known. Scheme design is partly based on non-ecological considerations and poses important restrictions on evaluation studies. We describe a robust approach to evaluate agri-environment schemes and use it to evaluate the biodiversity effects of agri-environment schemes in five European countries. We compared species density of vascular plants, birds, bees, grasshoppers and crickets, and spiders on 202 paired fields, one with an agri-environment scheme, the other conventionally managed. In all countries, agri-environment schemes had marginal to moderately positive effects on biodiversity. However, uncommon species benefited in only two of five countries and species listed in Red Data Books rarely benefited from agri-environment schemes. Scheme objectives may need to differentiate between biodiversity of common species that can be enhanced with relatively simple modifications in farming practices and diversity or abundance of endangered species which require more elaborate conservation measures.

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1. The annual cycle o f noctuid moths feeding as larvae on the foliage of eighteen woody plant species (belonging to ten different families) was studied at two southeastern Spanish Mediterranean forest habitats. Two questions were addressed in this study. ( I ) Does the rigorous (hot and dry) summer season characteristic of the Mediterranean-type climate impose a constraint o n noctuid life histories? (2) Are there detectable differences in abundance or phenological patterns between the noctuid assemblages feeding on evergreen and winterdeciduous trees and shrubs?2 . Regardless of their leaf persistence habit, the majority of woody species studied had short shoot growth and leaf production periods in spring. Abundance of noctuid larvae peaked in May-June, shortly after host plants started to produce new leaves. Virtually no noctuid larvae were found o n the foliage of the woody species studied at other times of year. Abundance and seasonal pattern of occurrence of larvae were similar on evergreen and deciduous food plants.3 . In contrast with the unimodal seasonal pattern exhibited by larvae. the abundance of adult moths (assessed by light trapping) showed two distinct peaks in early summer and early autumn, and a marked minimum in mid-summer. 4. Most woody plant-feeding noctuids recorded in this study (86% o f species, about 95% of individuals) were univoltine. Univoltine species fell into one of two distinct life history categories. corresponding to pre-and post-summer flight periods. These two contrasting phenologies were associated with a bimodality in the duration of the pupal stage ('short' versus 'long'), and were closely related t o taxonomical affiliation at the subfamily level. 5 . Within the 'short' pupal duration group. some species mate and oviposit shortly after emergence and pass the dry season in the egg stage, while others remain as potentially active. non-reproductive adults over most of the summer and mate by the end of that season. Species in the 'long' pupal duration group pass the summer in pupal or prepupal stagc.6. In the Mediterranean habitats studied. the adversity of the summer dry season seems to have led to a woody plant-feeding noctuid species assemblage almost entirely made up ot univoltine species that concentrate their larval phases when suitable food (young leaves) is most abundant, and 'avoid' mid-summer as a flight time by emerging either shortly before o r shortly after the adverse summer drought period. Year-round foliage availability afforded by dominant evergreen plants docs not seem to have influenced the seasonal organization of noctuid cycles in any substantial way. Key words. Evergreen plants. herbivory. Lepitloptera. life history, Mediterranean forcst, Mediterranean climate. Noctuidac, phenology. se;isonn I i t y . Corrc\pondcncc: Dr J . L. Ycla. Eqiicioii t3ioldgic.a dc Doilaiia. ('.%I ( ' . . Apariado 10%. F-JIO,YI) Scvilla. Spain 260 Josc; L . Yelu utid Curlos M. Herreru